ES3003833T3 - Machine for removing formwork from ceiling structure - Google Patents

Abstract

A machine for removing formwork from beneath a cured concrete slab includes a wheeled base movable on and supported by a support structure, a raise-and-lower structure disposed on the wheeled base, and a formwork removal device attached to the raise-and-lower structure. The formwork removal device includes an arm extending from the raise-and-lower structure, at least one wedge member disposed at a distal end of the arm, and a formwork retaining mechanism. With the raise-and-lower structure adjusted to raise the wedge member and the wedge member moved to engage the formwork and an underside of a concrete slab, the wedge member is further moved to apply a force that separates part of the formwork from the concrete slab, and the formwork retaining mechanism is operated to grip the formwork separated from the concrete slab, retaining the formwork. With the formwork held in place by the formwork retaining mechanism, the lifting and folding structure is lowered, removing the formwork from the concrete slab. (Automatic translation with Google Translate, no legal value)

Description

DESCRIPTION

Machine for removing formwork from the roof structure

Cross-reference to related applications

This application claims the benefit of deposit of U.S. Provisional Application Ser. No. 63/198,227, filed October 5, 2020, U.S. Provisional Application Ser. No. 62/705,839, filed July 17, 2020, and U.S. Provisional Application Ser. No. 62/947,663, filed December 13, 2019.

Field of the invention

The present invention relates generally to concrete structures and floors of buildings and to methods of installing and removing beams and panels or forms used to form concrete structures and floors of buildings.

Background of the invention

Formwork includes molds or supports, whether temporary or permanent, into which concrete or similar materials are poured to create building walls and slabs. In known construction practice, formwork is mounted on a surface or lower floor level to form the next building level above. Once the concrete slab has hardened sufficiently, the formwork can be removed. Traditional plywood formwork is constructed on site, with the plywood panels supported by beams and formwork posts. It is easy to manufacture, but time-consuming and dangerous to construct and dismantle, especially for large structures. Document CN 205558288U discloses a machine according to the preamble of claim 1.

Summary of the invention

The present invention provides a machine according to claim 1 for the safe and efficient removal of panels and beams from formwork systems. The machine includes a motorized wheeled base having a elevating platform that can extend upwardly toward the formwork to be removed. The machine is adapted to remove plywood or formwork from the underside of a placed and cured slab or roof structure.

In accordance with one aspect of the present invention, the machine is operable to remove plywood formwork from the bottom of a concrete slab. The machine includes a formwork stripping apparatus, which is attached to the elevating platform, and which includes an arm, a wedge member, and a formwork retaining mechanism. The wedge member includes one or more wedges attached to the arm. As the machine is maneuvered, the wedge mechanism engages the formwork, applying a separating force to partially separate or release the formwork from the slab. As the formwork is partially separated or released, the formwork retaining mechanism secures the partially separated formwork on the arm to remove the formwork and move the removed formwork to a designated location where it can be stacked and/or stored for reuse.

In accordance with another aspect of the present invention, the machine provides a beam removal apparatus. The beam removal apparatus includes an arm and a beam clamping mechanism. The beam clamping mechanism may comprise a gripper that fits over the center section of an I-beam and grips it. Optionally, the beam removal apparatus may include a rotary actuator so that the gripper can grip the beam and the rotary actuator can twist the beam to release the beam for removal. The machine can reposition the removed beam and can stack the removed beams in a predetermined location.

These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.

Brief description of the figures

FIGS. 1 and 2 are perspective views of a stripping machine for removing plywood forms, shown with a lifting frame extended to a raised or extended position and a gripping member in an open state;

FIG. 3 is a side view of the formwork stripping machine of FIGS. 1 and 2;

FIG 4 is another perspective view of the stripping machine, shown with the gripping element in the closed state;

FIG 5 is another side view of the stripping machine, shown with the boom in the extended position;

FIG. 6 is another side view of the stripping machine, shown with the boom in an extended position and the gripping device tilted downward relative to a support structure by a hydraulic actuator; FIG. 7 is a perspective view of the stripping machine of FIG. 6;

FIGS. 8A and 8B are enlarged partial side views of the stripping machine, shown with the gripping member in the open state;

FIGS. 9A and 9B are enlarged partial side views of the stripping machine, shown with the boom in the extended position, the gripping member in the closed state, and the gripping device inclined downwards with respect to the support structure;

FIG 10 is a partial perspective view of the form stripping machine, shown with the gripping element in the closed state;

FIG 11 is a partial perspective view of a form stripping machine, shown with the boom in the extended position;

FIGS. 12 and 13 are perspective views of the stripping machine, shown with the lifting structure retracted to a lowered or stowed position;

FIG 14 is a side view of the formwork stripping machine of FIGS. 12 and 13;

FIGS. 15 and 16 are perspective views of the stripping machine, shown with the boom in an extended position and the gripping device inclined downwards relative to the support structure;

FIG 17 is a side view of the formwork stripping machine of FIGS. 15 and 16;

FIG 18 is a perspective view of the stripping machine, shown with the boom in an extended position and the gripping device tilted upward relative to a support structure;

FIG. 19 is a perspective view of the form stripping machine of FIG. 18, shown with the gripping device tilted downward relative to the support structure;

FIGS. 20 and 21 are perspective views of another stripping machine for removing plywood forms, shown with its lifting frame extended to a raised or extended position; FIG. 22 is a perspective view of the stripping machine of FIGS. 20 and 21, shown with a lifting frame retracted to a lowered or stowed position;

FIG. 23 is a side view of the form stripping machine of FIG. 22;

FIG. 24 is a perspective view of the stripping machine of FIGS. 22 and 23, shown with a gripping device in the open state and a piece of plywood formwork resting on a floor surface;

FIG. 25 is a side view of another stripping machine for stripping plywood, shown with a boom for extending a wedge member relative to the lifting structure;

FIGS. 26A and 26B are partial perspective and side views of a double-wedge mechanism and a receiving and holding mechanism of a form-stripping machine;

FIGS. 27A and 27B are side views of the double-wedge mechanism of FIGS. 26A and 26B, shown in two stages of removal from the plywood formwork of a concrete roof structure;

FIG. 28 is a side view of another stripping machine, not in accordance with the present invention, shown with a spring-loaded arm and wedge for stripping plywood from a concrete roof structure; FIGS. 29-32 are perspective views of a stripping machine, not in accordance with the present invention, shown with a pneumatic plywood gripper on a lift-and-loop frame with a wheeled base;

FIGS. 33-35 are perspective views of a stripping machine for removing beams from formwork, not in accordance with the present invention, shown with a beam grapple on a lift-and-loop structure on a wheeled base, a boom in an extended position, and an arm inclined upwardly relative to a support structure;

FIG 36 is a side view of the form stripping machine of FIGS. 33-35;

FIGS. 37-39 are perspective views of a stripping machine for removing beams from formwork, not in accordance with the present invention, shown with a beam gripper on a telescopic arm of a wheeled base, the telescopic arm in an extended position;

FIG 40 is a side view of the form stripping machine of FIGS. 37-39;

FIGS. 41A-C is another perspective view of the form stripping machine of FIGS. 37-40;

FIG 42 is a perspective view of another stripping machine for removing formwork beams; not according to the present invention, and

FIG 43 is a view of a control panel of a form stripping machine.

Detailed description

To create poured concrete slabs for buildings, workers assemble formwork panels to define spaces that are then filled with concrete. The formwork panels, typically consisting of individual sheets of plywood supported by beams, support the poured concrete until the slab or wall has hardened sufficiently, at which point workers remove the formwork for waste or reuse. For example, workers may remove the formwork from one level of a multi-story building after the concrete hardens and use the formwork to form the next higher level of the building. Traditionally, workers assemble the formwork for the upper slabs using plywood panels supported from below by a system of beams that support the weight of the poured concrete as it hardens. The beams, in turn, are supported by shoring posts that rest on a firm foundation, such as a lower-level slab. When the upper level slab hardens sufficiently, workers manually dismantle and remove the beams supporting the plywood panels, then pull or pry the formwork panels free from the bottom or underside of the slab. This procedure is tedious and time-consuming and exposes workers to hazards, such as falling material. The formwork stripping and/or beam stripping machines of the present disclosure streamline this procedure, reducing costs while increasing worker safety.

Referring to FIGS. 1-7, a formwork stripping machine or device 110 for removing panels and beams from formwork systems includes a motorized wheeled base 111, a lifting mechanism 112 disposed on the wheeled base 111, and a formwork stripping apparatus or device 114 coupled to the lifting mechanism 112 for removing the formwork. For the purposes of the present disclosure, the term "formwork" may refer to plywood sheets, support beams, or other materials applicable in the context of use.

The wheeled base 111 has four wheels, which may be independently driven wheels, and which may be independently steered, allowing for a high degree of maneuverability on the jobsite. Each of the four wheels may be steered, for example, by pivoting around a vertical axis and having independent steering mechanisms. Optionally, the front wheels and/or rear wheels may be steered in tandem, for example, by connecting both front and/or rear wheels to an axle. Optionally, other wheeled configurations may be used, such as, for example, a three-wheeled base or a base having more than four wheels, or a base propelled by tracks driven by caster wheels.

In the illustrated embodiment, the lifting mechanism 112 comprises a scissor lift having a plurality of pivotally connected sections pivoted relative to one another to raise and lower the form removal device by extending and retracting a hydraulic cylinder 112a disposed in the base 111. The scissor lift, when extended or raised, lifts or moves the form stripping device 114 from a position proximate or abutting the base 111 (FIGS. 12-17) to a position at or near the formwork (FIGS. 1-7) to remove the formwork from the underside of the concrete slab, as explained below. The scissor lift, when retracted (as shown in FIGS. 12-17), folds into a compact configuration on or above the wheeled base 111, with the stripping device 114 lowered to the lowered or retracted state. As shown in FIGS. 12-17, the liftable structure 112, when lowered or retracted, may be at least partially stored within a cavity of the wheeled base 111, such that the machine 110 may be more compact for storage or maneuverability. The liftable structure 112 may also maintain a variety of different height positions, as illustrated in FIGS. 18 and 19, in order to reach forms at different heights from the wheeled base 111.

As shown in FIGS. 5-7 , the form stripping device 114 is mounted to the lifting mechanism 112 on an extendable and retractable boom 115 that is extendable by actuation of an actuator 115a, such as, for example, a hydraulic cylinder or the like. The form stripping device 114 may also be mounted to the lifting mechanism 112 directly or to a platform, structure, or otherwise coupled to the lifting mechanism 112 opposite the base 111 such that when the lifting mechanism is extended or raised from a retracted or lowered state to an extended or raised state, the form stripping device 114 extends or raises away from the base 111.

Referring to FIGS. 8A-9B, the formwork stripping device 114 is configured to remove a formwork piece, a beam, or a plywood piece 116 from the bottom of a hardened concrete slab and to grip the removed plywood piece 116. The formwork stripping device 114 comprises a support portion or structure 118 that is fixed to the end of the boom 115, with a gripping device 119 pivotally mounted to the support portion 118 and/or the end of the boom 115. The gripping device 119 is pivoted up and down by an actuator 119a, such as, for example, a hydraulic cylinder or the like. The gripping device 119 includes a support structure or base 121 that is pivotally mounted to the support structure 118, and includes a wedge member 120 or mechanism extending from the support structure 121 to separate the formwork from the slab (in a manner to be described later) and a gripping member 122 or mechanism or arm that cooperates with the wedge member 120 to grip and hold the removed plywood 116.

The gripping member 122 is pivotally mounted to the support structure 121 and is pivoted relative to the wedge member 120 between an open state (FIGS. 8A and 8B) and a closed state (FIGS. 9A and 9B) via an actuator 122a, such as a hydraulic cylinder or the like. The gripping member 122 may pivot from an open state to a closed state such that the gripping member 122 engages the plywood piece 116 between the gripping member 122 and the support structure 121 or the wedge member 120, securing the plywood 116 in position. As best shown in FIGS. 8B and 9B, opposing surfaces or edges of gripping member 122 and wedge mechanism 120 may be serrated or toothed or knurled or roughened or otherwise configured to enhance gripping of plywood formwork piece 116 being clamped between gripping member 122 and wedge mechanism 120.

As shown in FIG. 10, the stripping device 114 also includes a support arm 123 extending from the gripping device 119 and pivoting with the support structure 121 of the gripping device 119 when the gripping device 119 is pivoted up and down by the actuator 119a. The support arm 123 may be removably coupled to the support structure 121 and is configured to support the removed plywood 116 at a point spaced from where the plywood 116 is clamped between the gripping member 122 and the wedge member 120 or the support structure 121. At a distal end from where the support arm 123 is coupled to the support frame 121, the support arm 123 may comprise a rounded cross support member 124 such that a removed plywood piece 116 bears upon the rounded cross support 124 of the support arm 123. The rounded cross support 124 may comprise a disk or plate or folded bar substantially forming a cap over a distal end of the support arm 123 and extending horizontally from the support arm 123 to substantially form a T-shape. The rounded cross support 124 provides support to a removed plywood piece 116 to prevent twisting or bending or breakage of the removed plywood 116 during removal of the plywood 116 or movement or lifting or lowering of the stripping machine 110. The rounded cross support 124 also provides a rounded contact surface in order to reduce the possibility of the formwork 116 catching or snagging or tearing or ripping on an edge of the support arm 123.

Thus, the form stripping device 114 is operable to remove a formwork piece 116 from the bottom of a hardened concrete slab. For example, the form stripping machine 110 may be positioned substantially beneath a plywood formwork piece 116 connected to a hardened concrete slab (after the concrete slab has been placed on the plywood and has sufficiently cured and hardened). The lifting structure 112 can raise the stripping device 114 to a target height to engage the plywood 116, whereby the actuator 119a moves the gripping device 119 and pivots the gripping device 119 upward to engage the wedge member 120 with the plywood formwork piece 116, with the support arm 123 positioned on the formwork 116 with its distal support end spaced from the wedge member 120.

When positioned with the wedge member 120 in the form, the gripping device 119 may be extended to move the wedge member 120 to dislodge the form. For example, the boom actuator 115a may extend the boom 115 to apply a force to the plywood 116 at the wedge member 120, whereby the gripping member 122 is pivoted to grip or hold the form 116 between the gripping member 122 and the bottom of the wedge member 120 or the support structure 121, with the support arm 123 supporting a distal portion of the form 116. The device 114 (while holding the removed form) may be lowered by lowering the elevating structure 112 and the gripping device 119 may be pivoted downward (such as in FIGS.

6 and 7) with respect to the support structure 118 at the end of the boom 115 and the gripping member 122 can pivot to its open position to release and drop the removed formwork 116.

Referring to FIGS. 20-24 , a further embodiment of the stripping machine 210 is provided for removing form panels and beams. The stripping machine 210 may include similar aspects and functions of the stripping machines discussed throughout this disclosure such that a full description of the aspects of the machines need not be repeated herein. It should be understood that the multiple possible embodiments of the stripping machine may include or exclude elements contained within one or any combination of the illustrated embodiments provided by this disclosure. The stripping machine 210 includes a motorized base 211 with wheels. The base 211 has four independent motorized wheels, each of which can be steered by pivoting about independent vertical axes. Optionally, the front wheels and/or the rear wheels can be steered in tandem, for example, by connecting the front wheels and/or the rear wheels by axles. Optionally, other wheeled configurations may be used, such as, for example, a three-wheeled base or a base having more than four wheels, or a base propelled by tracks driven by rotationally driven wheels. The formwork stripping machine 210 includes a lifting frame 212 disposed on the wheeled base 211, with a formwork stripping apparatus or device 214 coupled to the lifting frame 212 for removing forms and/or beams.

In the illustrated embodiment, the liftable structure 212, similar to the liftable structure 112, comprises a scissor lift having a plurality of pivotally connected sections pivoted relative to one another to raise and lower the structure by extension and retraction of a hydraulic cylinder 212a in the base 211. The scissor lift, when extended or raised, as shown in FIGS. 20 and 21, raises or moves the form stripping device 214 into position on the form or plywood 216 for removing the form from the bottom of the slab. The scissor lift, when retracted, as shown in FIGS. 22-24, folds into a compact configuration on the wheeled base 211, with the form stripping device 214 lowered to the lowered or retracted state.

As shown in FIGS. 20-23 , the form stripping device 214 is configured to hold a piece of plywood formwork 216 that may have been removed from the bottom of a hardened concrete slab by the machine 210 at a height near a raised/extended position of the elevating structure 212. The form stripping device 214 includes an arm 218, a wedge mechanism 220 for separating the plywood 216 from the slab, and a retaining mechanism 222 for holding the removed plywood 216. The wedge mechanism 220 is positioned at the forward end of the arm 218, distal of where the arm 218 joins the lift structure 212, such that when the machine 210, with the lift structure extended or raised to position the wedge mechanism 220 on the plywood 216 and the concrete, moves forward, the wedge mechanism 220 engages the plywood 216 and is urged between the plywood and the concrete slab, applying a force to separate the plywood 216 from the concrete slab. Optionally, the arm 218 may be extendable from the lift structure 212 by a hydraulic actuator 218a or an extendable boom or similar capability mechanism, as shown in FIG. 25. The hydraulic actuator 218a may allow the wedge mechanism 220 to extend greater distances from the lift structure 212. The hydraulic actuator 218a may also allow the wedge mechanism 220 (when raised so that the wedge member 220 is at the plywood 216 and the bottom of the slab) to engage the plywood 216 and move between the plywood and the concrete slab as the hydraulic actuator 218a extends forward, while the wheeled base 211 remains stationary so that the extending motion of the hydraulic actuator 218a, rather than the motion of the wheeled base 211, primarily creates the spreading force applied on the attached plywood 216 at the bottom of the concrete slab.

When the wedge mechanism 220 has been moved and positioned a sufficient amount at the interface between the plywood 216 and the concrete slab, the retaining mechanism 222 operates to clamp or grip the plywood 216 to remove the plywood 216 from the concrete slab and move the plywood 216 to a target location. The retaining mechanism 222 may include a hydraulically activated jaw that supports and clamps the plywood 216 after it is removed from the slab. For example, as can be seen in FIGS. 21-23, the retaining mechanism 222 includes a hydraulic actuator 222a (or other suitable drive device) extending to pivot a plywood engaging member into engagement with the plywood 216 to clamp the plywood 216 between the plywood engaging member and the arm 218. When the plywood is so clamped, the form-stripping device 214 may be lowered by lowering the elevating structure 212 to pull the plywood downward and further and completely remove the plywood 216 from the concrete slab.

In this way, the plywood 216 may be carefully lowered from the slab height to a suitable or target storage location. Optionally, and as shown in FIGS. 22 and 23, the machine 210 may lower the plywood 216 to a point near the ground surface by retracting the elevating platform 212 to a lowered position while the form-stripping device 214 continues to firmly hold the plywood 216. As shown in FIGS. 24, the machine 210 may open the retention mechanism 222 by retracting the hydraulic actuator 222a to release the removed plywood 216 to rest on the ground surface.

Optionally, and as shown in FIGS. 26A-27B , the stripping machine 210 may include a double-edged wedge mechanism 220 and a receiving and holding mechanism 222. As shown, the wedge mechanism 220 includes a pair of wedges or wedge-shaped members, each wedge positioned on one side of the forward or distal end of the arm 218, which may comprise a pair of arms spaced apart from each other, one on each wedge, such that each wedge engages the plywood 216 and the underside of the slab or roof in parallel. In this way, the separation force may be more evenly distributed across the plywood 216, reducing possible damage to the plywood 216. Additional wedges may be used to better distribute the removal forces.

The receiving and holding mechanism 222 includes a receiving shelf or structure positioned below the wedge mechanism 220 for receiving the removed or partially removed plywood 216, and a hydraulically activated clamping mechanism 222b for securing the removed plywood 216 to the receiving structure of the arm 218 and the holding mechanism 222, such as by clamping the plywood 216 against a portion of the arm 218 above the shelf or against the bottom of the receiving structure 222. Each wedge of the wedge mechanism 220 is attached to the forward end of the arm 218 in a structure that allows the wedge to pivot on the structure to engage the slab surface during removal of the plywood. Optionally, the center of gravity of the wedge may cause the wedge to pivot upward and maintain contact with the bottom of the slab so that, as the wedge system 220 advances, the tip of the wedge is forced between the slab and the formwork 216.

Optionally, and as shown in FIGS. 27A and 27B, the wedge members 220 may be biased by a torsion spring or other biasing means to pivot the wedges so that the tips of the wedge members 220 point partially upward toward the ceiling or hardened concrete slab and formwork. In this way, the wedge members 220 may be biased into a position or orientation where they are easily forced between the plywood 216 and the bottom of the concrete slab as the arm moves toward the plywood 216.

As shown in FIG. 27A, during operation of the stripping machine, the wedge mechanism 220 moves into engagement with the plywood 216 and the retaining concrete slab (illustrated as "Roof") such that the wedges can displace the plywood 216 from the concrete slab. As the stripping machine moves the wedge mechanism 220 deeper into the area between the plywood 216 and the concrete slab, the wedges work to pry or separate part of the plywood 216 from the concrete slab. As shown in FIGS. 27B, once the wedge mechanism 220 has been sufficiently positioned within and between the plywood 216 and the concrete slab such that part of the plywood 216 is received in the receiving and holding mechanism 222, the clamping mechanism 222b may be activated to engage the plywood 216. The clamping mechanism 222b may be activated by, for example, extending or retracting a hydraulic actuator connected to a clamping head, thereby pivoting the clamping head to engage and hold the plywood 216 between the clamping mechanism 222b and a portion of the arm 218 or between the clamping mechanism 222b and the holding mechanism 222. With the plywood 216 secured and held in the receiving and retaining mechanism 222, the stripping device 214 may be lowered and moved, for example, by lowering the extendable frame 212 and maneuvering the wheeled stand, to remove the plywood 216 from the concrete slab. After the plywood 216 is removed, the stripping machine 210 moves the plywood 216 to a target location, whereupon the hydraulic actuator retracts to release the plywood 216, allowing the removed plywood 216 to be placed in the target location.

As shown in FIGS. 27A and 27B, the receiving and retaining mechanism 222 is configured to receive a portion of the plywood 216 therein as the wedges 220 space part of the plywood 216 from the concrete. The length of the receiving portion may be selected to receive an end portion of the plywood 216 therein, or may be sized to receive a larger portion of the plywood 216. Optionally, and as shown in FIG. 25, the receiving portion may be sized to receive a substantial portion, such as half of an 8-foot length of plywood therein. Optionally, with a larger receiving portion, the clamping mechanism 222b may comprise two clamping elements or may have an inner clamping element spring-loaded or otherwise biased to apply a holding force on the plywood 216 when the plywood 216 has been sufficiently received in the receiving portion with the outer clamping element having an actuator to clamp the plywood at the outer end of the receiving structure. Optionally, the arm 218 and wedge mechanism 220 may be extendable relative to the bottom of the receiving portion, as shown in FIG. 25, by a hydraulic actuator 218a or a linear actuator or the like which, when actuated, moves or extends/retracts the wedge mechanism 220 relative to the receiving and clamping portion 222.

Thus, the stripping machine operates to separate the plywood 216 from the underside of a concrete slab or ceiling in an automated, safe, and efficient manner, without requiring an operator to manually remove the plywood 216. The machine 210 engages the plywood 216 and pulls it down from the underside of the concrete slab and can easily move the removed plywood 216 to a desired location, such as a floor surface or a rack or cart or the like. The stripping device 210 includes one or more wedges 220 that operate to separate a portion of the plywood 216 from the concrete slab, whereupon a clamping or holding device 222 is actuated to grip the plywood 216 to forcibly remove the plywood 216 from the concrete slab.

Optionally, arm 218, including wedge 220 at the distal end of the arm from the liftable structure 212, may be pivotally mounted to the liftable structure 212 and may pivot upwardly from the liftable structure 212, as shown in FIG. 28. In such an application, an upward force, which may be applied by a spring 220a or other biasing element, causes the boom 218 and wedge 220 to be urged upward and engage the concrete slab such that the wedge is forced between the plywood 216 and the concrete slab as the boom 218 moves toward the plywood 216. Optionally, the elevating structure 212 may comprise any suitable mechanism for raising/extending or lowering/retracting the boom 218 and the plywood removal device 214. For example, the elevating structure 212 may comprise a telescoping boom or an articulated boom or the like that extends or retracts or adjusts in response to one or more hydraulic actuators or the like (such as a boom and controls utilizing aspects of the arms and booms and controls described in U.S. Pat. No. 10,190,268 which is incorporated herein by reference). reference in its entire extension. Optionally, the arm 218 may be raised and lowered by a manually operated hydraulic lift or jack. For example, the wheeled base 211 may be a wheeled base or machine, such as a forklift or order picking machine, optionally with a platform or other receptacle or container or the like beneath the stripping device for the plywood 216 to fall onto as it is removed.

The wheeled machine 210 can be sized to easily maneuver between shoring posts while removing beams and formwork. The wheeled machine 210 can also be compactly stored when not in operation. During operation, the wheeled machine 210 can be remotely controlled, such as by an operator controlling the machine via a handheld remote control that is in wireless communication with the wheeled machine 210, further increasing worker safety. Optionally, the wheeled machine 210 can pull a trailer on which the removed formwork can be stacked and stored, for example, to allow for efficient transport from the jobsite.

Optionally, and as shown in FIGS. 29-32 , a stripping machine 310 may include a plywood gripping device 324 comprising a pneumatically actuated gripper 324a attached to an articulating and/or extendable arm 326. The arm may extend from a scissor lift, such as a lift similar to the elevating structure 112 or elevating structure 212 discussed above, which is elevatable to position the gripper 324 on the underside of the plywood 316 to firmly engage the gripping elements 324a of the gripper on the plywood 316 from below. The wheeled base and lifting mechanism of the machine 310 may be substantially similar to the bases and mechanisms of the machines 110, 210 discussed above, so that a detailed discussion of these aspects of the machines need not be repeated herein.

When the gripper 324 engages the underside of the plywood 316, the gripper 324 may be activated to generate suction on the plywood 316 to secure the plywood 316 to the gripper 324a. The gripper 324 is then lowered, for example, by retracting the arm 326 or lowering the lifting structure, releasing the formwork or plywood 316 from the underside of the concrete slab or roof. As shown in FIGS. 29 and 30, after the formwork 316 is removed, the gripper 324 continues to hold the plywood 316 while the arm 326 lowers or otherwise repositions the plywood 316, such as to move and orient the plywood 316 to a target location, whereby the gripper 324a is deactivated to release the plywood 316 for storing or stacking the plywood 316 at a target location. As shown in FIGS. 29-32, the gripper 324 is pivoted relative to the end of the arm 326 via an actuator 326a such that the gripper may initially be positioned to face upward toward the formwork (FIGS. 31 and 32), and then, after the formwork is removed, may be pivoted to face generally downward (FIGS. 29 and 30) to release the formwork at the intended location.

When removing formwork or plywood from beneath a cured concrete slab or roof structure, at least some of the support beams and posts supporting the plywood or holding the plywood in place must be removed prior to removing the plywood. Optionally, and now referring to FIGS. 33-41B, a form stripping or beam removing machine 430 includes an arm 432, which is mounted on a wheeled base 431, similar to a wheeled base 111 or 211 or 311 described above, and a gripping mechanism 434 positioned at a distal or beam end of the arm 432. The gripping mechanism 434 includes a pair of pivoting jaws having a gripping surface that engages the center section of an I-beam 435.

As shown in FIGS. 33-36 , the arm 432 may be mounted on a lift structure 433, such as a scissor lift structure or the like, similar to the lift structure 112 or 212 as described above, which is mounted on the base 431. Optionally, and as shown in FIGS. 37-41C , the arm 432 may be mounted on one end of an articulating and/or extendable arm 437 that is mounted on the wheeled base 431. The lift structure 433 or arm 437 raises or extends and lowers or retracts the arm 432 and the gripping mechanism 434 to move the gripping mechanism 434 toward the beam to grip the beam 435 from below or from the side of the beam. In use, the gripping mechanism 434 would typically grip from below the beam 435 due to the presence of plywood and concrete on the top side of the beam 435.

In the exemplary embodiment shown in FIGS. 37-41C , arm 437 comprises an extendable and retractable arm having multiple sections that move relative to one another to extend or retract the arm and gripping mechanism 434. As shown in the illustrated embodiment, the arm sections 437, when extended, cantilever relative to the adjacent arm or section. During extension and retraction of arm 437, the arm sections are movable via rollers and supports at the inner or proximal end of the respective arm section that engage and move along the adjacent arm section. Such movement may be responsive to actuation of a cable or chain that imparts movement of the distal or outermost section of the arm relative to the base 431, such as, for example, by pulling the support at the inner or proximal end of the arm 437 toward the outer or distal end of the adjacent section of the arm, or such as by rotary actuation of rollers or other suitable means.

The gripping mechanism 434 is pivotally mounted to the distal end of the arm 432, which is pivotally mounted to the end of the extendable arm 437, and which is pivotable relative to the arm 437 by a hydraulic actuator 436 or other drive means. Optionally, and with reference to FIGS. 33-36, the gripping mechanism arm 432 may be pivotally mounted to a support structure 418 at an upper end of the elevating structure 433, with the support structure 418 mounted to an extendable boom 415 similar to similar elements described above (see, e.g., support structure 118 and boom 115), such that a detailed discussion of the support structure need not be repeated herein. The gripping mechanism 434 may be coupled to another hydraulic actuator 438, or other actuating means, which extends and retracts to close and open the jaws of the gripping mechanism.

Because the beams may be nailed or otherwise secured to the formwork, the gripping mechanism 434 may also include a rotary actuator 440 that rotates the jaws to apply a torque to the beam, when the beam is gripped between the jaws, to release the beam for removal. As can be seen in FIGS. 41A-C , the rotary actuator 440 may comprise a motor, such as a hydraulically driven motor, that rotationally drives a gear 440a which, in turn, rotationally drives a gear 440b at the base of the jaws, such as through a chain or linkage not shown, to rotate the gripping mechanism 434 about the longitudinal axis of the actuator 438. Once the beam has been released from the plywood or formwork and removed, the arm 432 and either the liftable structure 433 or the arm 437 may be repositioned to lower the removed beam 435. The gripping mechanism 434 may be opened to release the lowered beam 435 and allow it to drop onto the floor surface or other suitable storage location.

Optionally, and as shown in FIG. 42, the gripping mechanism 434' may be rotatably and adjustably mounted on the end of an arm 437' comprising two or more telescoping arms 437a' or sections that are telescopically extendable and retractable, such as through a hydraulic actuator or cables or chains or the like disposed within or otherwise along at least one of the telescoping arm sections. In the illustrated embodiment, a proximal end of the telescoping arm sections 437a' is pivotally mounted to a distal end of a base arm 437b', which has a proximal end that is pivotally mounted to the wheeled base 431'. The base arm is pivotally mounted to a rotatable base 437c' that rotates about a generally vertical axis relative to the wheeled base 431', such as by a rotatable drive device or system on the base, and the base arm 437b' pivots about a generally horizontal axis relative to the base 437c' by extension and retraction of an actuator on the base 437c'. Similarly, the telescoping arms 437a' pivot about a generally horizontal axis relative to the base arm 437b' by extension and retraction of an actuator between the base arm 437b' and the proximal telescoping arm.

Thus, the gripping mechanism 434' may be moved or maneuvered to any location by moving the wheeled unit and then adjusting the angles and orientation of the rotatable base 437c' and arms 437a', 437b'. The gripping mechanism 434' is rotatably mounted to the distal end of the telescoping arms 437a' and may rotate about a pivot axis that is normal to the longitudinal axis of the telescoping arms 437a', such as through a bracket mounting the gripping mechanism to the distal end of the arm, and the jaws 434a' of the gripping mechanism may also rotate about another pivot axis that is normal to the pivot axis of the bracket at the end of the arm. Thus, the jaws 434a' may be maneuvered to position the jaws 434a' on the beam, whereby the jaws 434a' may be clamped on the beam to remove the beam.

Optionally, the wheeled base or support unit may have a lifting/lowering device or structure, with an attachment portion or head at an upper end of the lifting/lowering device configured for detachable attachment of the mechanism and the holding mechanism or gripping mechanism, such that the machine may be adapted to remove plywood from the underside of the concrete slab or ceiling and to remove support posts and beams from the underside of the concrete slab or ceiling. Thus, a single machine may be used for both formwork stripping procedures, by changing the formwork engagement device or mechanism to adapt the machine to the respective procedure.

As shown in FIG. 29, the machine may include a control panel 50 that provides the operator with controls for raising and lowering the removal device and for extending the device and pivoting the device and gripping and releasing the formwork, by extending and retracting respective actuators or hydraulic cylinders. For example, the control panel 50 may include a combination of controls affecting one or more of raising and lowering the lifting mechanism from the base, extending and retracting the boom upon which the formwork removal device is mounted toward and away from the lifting mechanism, tilting the formwork removal device up and down with respect to the arm or boom or support structure, and opening and closing the gripping mechanism with respect to the wedge member or support structure. The control panel 50 also provides controls for controlling the operation of the wheeled stand so that the operator can maneuver the wheeled stand to a desired location before and/or after the removal device removes the formwork. In the illustrated embodiment, the control panel 50 includes a joystick 52 for the operator to control the tilt of the head, boom, and gripper or clamp. However, it should be understood that the control panel may include pushbuttons, slide switches, touch screens, or any other element configured to direct the movements of the stripping machine.

During operation of the machine, the controls may limit the propulsion speed of the wheeled stand if the scissor lift mechanism is raised, such as, for example, in response to a sensor on the lift mechanism. The controls may also limit the propulsion speed of the wheeled stand if the machine is on an angled propulsion or support surface, for example, such as in response to a level sensor on the wheeled stand. The controls may also limit the lifting speed of the lift mechanism as it approaches the ceiling and approaches its working height, for example, such as in response to a distance sensing sensor (such as an ultrasonic or similar sensor) on a top of the lift mechanism or another sensor that determines when the lift mechanism is approaching the proper working height. The controls may also disable the lifting function of the lift mechanism if the machine is on an inclined support surface, for example, such as in response to a level sensor on the wheeled stand.

After the operator has used the stripping machine to remove a formwork element, the operator may actuate a start or return button or switch or input on the control panel 50 (such as at the end of one of the levers or elsewhere on the control panel) to automatically return the machine to its initial or home settings to place the head tilt, boom, and gripper in their positions ready for the next removal or stripping cycle. For example, the operator may press and hold a reset button to initiate the sequence that (i) actuates the head tilt up function for an adjustable time, (ii) actuates the boom retract function for an adjustable time or until the boom limit switch is activated, and (iii) actuates the gripper open for an adjustable time, whereupon the boom will retract and the head will tilt up with the jaws open, in order to be ready for the next removal or disassembly cycle. When the reset sequence is active, the sequence can be stopped by pressing the reset pushbutton again. Actuating the head, arm, or gripper tilt lever above an adjustable threshold will also stop the sequence. A joystick can be ignored below this threshold, so that the return or home sequence is not stopped if a slight bump or similar action occurs on any of the levers.

Optionally, the formwork removal device or beam removal device can be selectively coupled to the machine or motorized wheeled base and selectively positioned in an operational position to perform the desired or selected task. That is, the mechanisms can be interchanged on a common or universal base 111 or 211 or 431 and/or a raise/lower or extend/retract structure 112 or 212 or 433 or 437 on the base. For example, once the slab has hardened, workers can couple the beam removal device to the elevating structure of the wheeled base to dismantle and remove the beams supporting the formwork. Once the beams are removed, workers can remove the beam removal device and couple the formwork removal device to the elevating structure of the wheeled base to remove the formwork or plywood from the slab. Optionally, the beam removal mechanism may be mounted at one end of the lifting structure and the formwork removal device may be mounted at the opposite end of the lifting structure, so that a single machine is selectively actuated to perform the desired operation.

During operation of the machine, an operator can remotely operate the wheeled base, equipped with a beam removal device, at the job site, such as by means of a remote controller that can control the drive and direction of the wheels, the extension/retraction of the elevating structure, and the rotation/locking/unlocking of the clamping device. The operator remotely controls the beam removal device to sequentially remove each formwork beam by grasping each beam from below, rotating the beam to free it from nails or other fasteners and plywood, repositioning the beam, and releasing the beam at a designated location, such as on a trailer pulled by the wheeled base. As needed, the operator maneuvers the powered wheeled machine between the remaining shoring posts to gain access to the next beam in the sequence. Optionally, the beam removal device may also be used to remove some of the vertical posts by grasping the posts and (such as after the posts are adjusted to be lowered from the beams) lifting and moving the posts to a desired or target location.

Once the beams are removed, the operator can remotely control the wheeled machine to transport the beams, on the trailer or other storage platform, off the job site. Operators can then equip or adapt the wheeled machine with the formwork and stripping device and remotely control the wheeled machine and the formwork and stripping device to sequentially remove the formwork or plywood from the underside of the concrete slab or roof structure. The operator, using the remote control, can extend the lifting structure so that the wedge mechanism contacts the hardened slab and then advance the powered wheeled machine, causing the wedge mechanism to engage the plywood and separate part of it from the concrete slab. As the wedge mechanism releases the plywood, the operator remotely controls the gripping mechanism to grasp and retain the removed plywood. The operator then remotely operates the motorized wheeled machine and formwork stripping device to lower and position the plywood and release it at a designated location, such as on a trailer, if applicable.

Operator control of the machine can be achieved through a wireless remote controller, which has multiple controls or inputs to allow the operator to control various motors and actuators of the machines. For example, the machine can have a gasoline engine that powers or drives a hydraulic pump to supply pressurized hydraulic fluid to the hydraulic motors and hydraulic actuators of the machine. For example, the controller can control the machine to hydraulically drive the steering mechanism and wheel drive motors to maneuver the base and the machine on the support surface or ground, and can separately control one or more hydraulic actuators to raise/lower or extend/retract the support structure on the base to raise/lower the device, such as the plywood removal device or the beam removal device, attached to the upper end of the support structure. The controller can also control one or more hydraulic actuators to extend or pivot or articulate the device and actuate the device to remove and move the plywood or beam.

Thus, a method for removing formwork from beneath a cured concrete slab includes providing a wheeled base movable over and supported by a support structure, a lift-and-fold structure disposed on the wheeled base, and a formwork-removing device attached to the lift-and-fold structure. The formwork-removing device comprises (i) an arm extending from the lift-and-fold structure, (ii) at least one wedge member disposed at a distal end of the arm, and (iii) a formwork retaining mechanism. The method includes moving the wheeled base along the support structure to position the machine below or near the formwork to be removed from the roof above the machine, and adjusting the lift-and-fold structure adjusted to raise the wedge member and position the wedge member at and in contact with the formwork and an underside of the concrete slab. With the lifting and lowering structure adjusted to raise the wedge member and with the wedge member positioned to engage the formwork and a bottom portion of a concrete slab, the method includes moving the wedge member relative to the formwork to apply a separating force to separate part of the formwork from the bottom portion of the concrete slab. With the wedge member coupled to the formwork and the bottom portion of the concrete slab, the method includes actuating the formwork retaining mechanism to grip the portion of the formwork that is separated from the bottom portion of the concrete slab to retain the formwork in the formwork removal device. With the formwork gripped by the formwork retaining mechanism, the method includes lowering the lifting and lowering structure to remove the formwork from the bottom portion of the concrete slab. The machine can be moved to a delivery location where the formwork retaining mechanism is actuated to release the formwork portion and drop the removed formwork at the intended delivery location.

Furthermore, a method for removing beams from beneath formwork at the bottom of a cured concrete slab includes a movable wheeled base supported by a support structure, a lift-up and fold-down structure disposed on the wheeled base, and a beam removing device coupled to the lift-up and fold-down structure. The beam removing device comprises a beam securing mechanism. The method includes moving the wheeled base along the support structure to position the machine below or near a beam to be removed from the ceiling above the machine, and adjusting the adjusted lift-up and fold-down structure to raise the beam removing device and position the beam removing device on the beam at a bottom of the concrete slab. With the lifting and lowering structure raised to position the beam removal device on the beam supporting the formwork at the bottom of the concrete slab, the method includes actuating the beam gripping mechanism to grip the beam and, with the beam gripped by the beam gripping mechanism, actuating the machine to remove the beam from the formwork (such as by rotating and/or lowering the beam gripping mechanism with the beam gripped there). With the removed beam gripped by the beam retaining mechanism, the method includes lowering the lifting and lowering structure. The machine may travel to a delivery point where the beam retaining mechanism is actuated to release the removed beam and drop it off at the intended delivery point.

Optionally, the machine can be operated to facilitate formwork installation before the concrete is placed and cured. For example, the machine can lift or raise beams into position at the tops of posts, and/or the machine can lift or raise plywood panels into position on top of the beams before the concrete slab is poured. The operator can remotely control the beam removal device to sequentially install each formwork beam by grabbing each beam from its stored location and raising/repositioning the beam to fit with the previously installed shoring beams or posts, then releasing the gripping mechanism. Similarly, the operator can remotely control the formwork stripping device to hold the plywood formwork in its gripping mechanism and raise/reposition the plywood formwork to its installation point for installation.

The positioning of the beams and/or plywood panels at the top ends of the posts may be responsive, at least in part, to a laser leveling device to ensure that the beams and plywood are at the proper height and level. Such laser leveling devices utilize a laser plane generator and laser receivers, which may be arranged on the beam or stripping device and/or on the elevating/detachable structure, to determine when the laser receiver(s) are at a particular height or level corresponding to the generated laser plane, effectively setting the height of the device to an appropriate or selected height for its particular function, and may utilize aspects of the systems described in U.S. Pat. Nos. 4,655,633; 4,930,935; 6,976,805; 7,044,681; 7,121,762; 7,144,191; 7,195,423 and/or 7,396,186. Optionally, during the removal procedure(s), the positioning of the removal devices may respond, at least in part, to said laser leveling system.

Changes and modifications in the specifically described embodiments may be made without departing from the principles of the present invention, which is limited only by the scope of the appended claims.

Claims (13)

1. A machine (110,210) for stripping formwork from below a cured concrete slab, the machine comprising: a base (111,211) with wheels that can be moved and is supported on a support structure a lifting and folding structure (112,212) arranged on the base with wheels a formwork stripping device (114,214) attached to the lift-and-fold structure, comprising (i) an arm (115,118,215,218) extending from the lift-and-fold structure, (ii) at least one wedge member (120,220) disposed at a distal end of the arm, and (iii) a formwork retaining mechanism (122,222); wherein the lift-and-fold structure is adjusted to raise the wedge member and when the wedge member is positioned to engage the formwork and a bottom of a concrete slab, the wedge member is moved relative to the formwork to apply a separating force to separate part of the formwork from the bottom of the concrete slab; characterized in that, when the wedge element is engaged with the formwork and the bottom of the concrete slab, the formwork retaining mechanism is actuated to grip the part of the formwork that is spaced from the bottom of the concrete slab to retain the formwork in the formwork withdrawal device; and When the formwork is grasped by the formwork retaining mechanism, the lifting and lowering structure descends to remove the formwork from the bottom of the concrete slab. 2. The machine of claim 1, wherein the wedge element is pivotally mounted on the arm. 3. The machine of claim 2, wherein the wedge member is biased to pivot so that a plywood end of the wedge member points partially upward. 4. The machine of claim 1, wherein the formwork retaining mechanism comprises a clamping mechanism that, when activated, secures the formwork to the formwork removal device. 5. The machine of claim 1, wherein the arm comprises one selected from the group consisting of (i) an extendable and retractable arm and (ii) an articulated arm. 6. The machine of claim 1, wherein the wheeled base, the lifting and folding structure and the formwork retention mechanism are actuated by a remote controller that is in wireless communication with the machine. 7. The machine of claim 1, wherein the wheeled base, the lifting and folding structure, and the formwork retention mechanism are operated via an operator interface on the machine, and wherein the operator interface is operated via an operator mounted on the machine. 8. The machine of claim 1, further comprising a beam withdrawing device coupled to the lifting and folding structure, wherein the beam withdrawing device comprises a beam gripping mechanism, and wherein the beam gripping mechanism operates to grip a beam supporting the formwork at the bottom of the concrete slab. 9. The machine of claim 8, wherein the beam gripping mechanism comprises a pair of jaws that can be closed to grip the beam. 10. The machine of claim 8, wherein the beam gripping mechanism comprises a rotary actuator, and wherein the rotary actuator, when activated, rotates the beam gripping mechanism to apply a torque force to the beam gripping mechanism and to the beam gripped by the beam gripping mechanism. 11. The machine of claim 1, wherein the wheeled base comprises at least three wheels, and wherein at least one of the wheels is steerable to steer the wheeled base while at least one of the wheels is rotatable to move the machine on the support structure. 12. The machine of claim 1, wherein the wheeled base comprises one or more tracks disposed on respective wheels, and wherein the one or more tracks, when driven by the wheels of the wheeled base, move the machine on the support structure. 13. The machine of claim 1, further comprising a receptacle disposed below the stripping device for receiving the formwork that is separated from the bottom of the concrete slab and is released by the formwork retention mechanism.